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8th Grade Math - Representing Constant Rate of Change

Clip 11/17: Rate of Change: Lesson Part 2C


Antoinette Villarin transitions her students to a matching activity, having her students use a recording sheet she and Cecilio Dimas made to find matching graphs and explain their justifications for the match.

She distributes a stack of twelve graphs that represent the flow of liquid between containers, and challenges students to match the two graphs that show movement for a given pair of containers. She notes that for some cards, information has intentionally been left out, and recommends that students begin with the cards that have complete information.

She reminds her students that they are trying to build a mathematical argument, so they must explain to their partner why a given pair of cards is a match, and the partner in turn needs to agree or disagree with each explanation. Antoinette explains how to use the cards, reminding students to refer back to the sentence frames for conversation if they don’t know what to say.

Teacher Commentary

While my students are doing pair work, I definitely have posters to support their language — like sentence frames. Also, when we're learning new concepts, I’ll put up the key concepts as we are learning them and keep them there throughout the entire unit.

Sometimes, I'll just put it on the board, and I'll forget to put them on a poster, but it will pretty much stay there for all periods, just so that students can reference it. We write it as we're learning it. We'll do an activity, we'll learn it, then we'll pull the math out of it. As we're pulling the math out of it is when we'll start to record ideas and thinking.

Materials & Artifacts